1. Technical Field
Embodiments relate to a vision system. More particularly, embodiments relate to a vision system for inspecting and identifying defects in a bottle.
2. Description of the Related Art
In a related art field, there are several different systems for inspecting and identifying bottle defects. For example, in the related art, there may be a leak inspector (i.e., a human) that manually inspects bottles traveling through an assembly line. However, as there is a need for increasing the efficiency and output of a bottle assembly line, the leak inspector may not have enough time to thoroughly investigate and identify bottle defects. Further, if the bottle is not clear, the leak inspector may only be able to see defects on the surface of the bottle. However, defects of a bottle can occur both on the surface of the bottle and inside the bottle. As bottles are moving to lightweight plastic, more small defects are being introduced inside the bottle (i.e., unmelted resin or gel) rather than carbon char, dust, etc., on the outside of the bottle. Thus, the leak inspector may not have enough time to identify bottle defects. Also, the leak inspector may not be able to see the small defects that are being introduced inside the bottle.
In another example of the related art, to identify defects, a related art system can use a surface light and a camera to take pictures of a bottle. However, if the bottle is not clear, the camera would not be able to see defects inside the bottle. Therefore, the camera would only be able to see defects on the surface of the bottle. Thus, using only a surface light and a camera is not an effective way for detecting defects on the surface and inside the bottle.
In another example of the related art, line scan cameras can be used to see cross sectional sheets of a bottle. However, line scan cameras only work well with clear plastic bottles (such as polyethylene terephthalate, or PET), which allow for defects to be detected inside and outside the bottles. However, line scan cameras are not good for non-clear bottles. Further, if the bottle has a non-uniform texture, inaccurate defects may be detected by the line scan cameras. In other words, the line scan cameras may identify the non-uniform texture as a defect.
If small defects are not detected in the bottle containers, this could cause problems for the end customer. Usually, many bottles are shipped to the end customer, and are stacked on top of one another. If a small defect inside a bottle causes a leak, all of the contents could be leaked out, and could ruin the remaining bottles. Therefore, the end customer wants to reduce the number of defects in bottles. Thus, there is a need for a system which can detect defects inside and outside of the bottle. Further, the system must be able to adapt to bottles that are non-clear and have a non-uniform texture.